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Nancy B.G. Lassen
Alternate image for Nancy B.G. Lassen

Nancy B.G. Lassen

Counsel

nlassen@wwdlaw.com
215.656.3638

Philadelphia

1845 Walnut Street, 24th Floor Philadelphia, PA 19103

  • 17 Willig, Williams & Davidson Attorneys Named Among 2025 ‘Best Lawyers in America,’ Deborah Willig and Irwin Aronson Named ‘Lawyer of the Year’
  • 16 Willig, Williams & Davidson Attorneys Named Among 2024 ‘Best Lawyers in America’
  • 18 Willig, Williams & Davidson Attorneys Named 2023 PA Super Lawyers & Rising Stars
  • 14 Willig, Williams & Davidson Attorneys Named Among 2023 ‘Best Lawyers in America,’ Amy Rosenberger Named ‘Lawyer of the Year’ in Philadelphia in Labor Law for Unions
  • 13 Willig, Williams & Davidson Attorneys Named Among 2022 ‘Best Lawyers in America,’ Two Named ‘Lawyers of the Year’ in Employee Benefits, Union Law
  • 17 Willig, Williams & Davidson Attorneys Named 2021 PA Super Lawyers, Managing Partner Named Among Top Attorneys in State
  • Willig, Williams & Davidson Attorney Nancy Lassen Quoted in The Philadelphia Inquirer
  • 5 Willig, Williams & Davidson Attorneys Selected as 2021 ‘Women Leaders In The Law’
  • 15 Willig, Williams & Davidson Attorneys Named Among 2021 ‘Best Lawyers in America,’ Nancy B.G. Lassen Named ‘Lawyer of the Year’ in Philadelphia Labor Law
  • Labor Attorney Nan Lassen Quoted by Vox on Regulators’ Failures to Protect Workers from COVID-19 as States Reopen
  • Nancy B. G. Lassen Elected as Fellow of the College of Labor and Employment Lawyers
  • Willig, Williams & Davidson Partners Present Webinar on Emerging Risks for Resumption of Business Operations for PBI
  • Philly Port Workers Union Pushed for Safety Precautions
  • Workers Question ‘Are We Essential or Disposable?’
  • Labor Attorney Nancy Lassen talks to NBC 10 About the Coronavirus Pandemic Endangering Meat Plant Workers
  • Labor Attorney Nancy Lassen Discusses Coronavirus Exposures and How Employees Can Protect Their Rights
  • 16 Willig, Williams & Davidson Attorneys Named 2020 PA Super Lawyers and Rising Stars
  • Willig, Williams & Davidson Lawyers Named Among 2020 ‘Best Lawyers in America’
  • 14 Willig, Williams & Davidson Attorneys Named 2019 PA Super Lawyers and Rising Stars
  • 15 Willig, Williams & Davidson Attorneys Named Among 2019 ‘Best Lawyers in America’
  • 14 Willig, Williams & Davidson Attorneys Named 2018 PA Super Lawyers and Rising Stars
  • 14 Willig, Williams & Davidson Attorneys Named Among 2018 ‘Best Lawyers in America’
  • 13 Willig, Williams & Davidson Attorneys Named 2017 PA Super Lawyers and Rising Stars
  • Willig, Williams & Davidson Labor Lawyer Nancy B.G. Lassen provides insight on SEPTA Strike to WHYY and Newsworks
  • 12 Willig, Williams & Davidson Attorneys Named Among 2017 ‘Best Lawyers in America’
  • 12 Willig, Williams & Davidson Attorneys Named 2016 PA Super Lawyers and Rising Stars
  • 12 Willig, Williams & Davidson Attorneys Named to 2016 ‘Best Lawyers in America’
  • 11 Willig, Williams & Davidson Attorneys Named 2015 PA Super Lawyers and Rising Stars
  • Game Change: NLRB Permits College Football Players to Elect a Union
  • 17 Willig, Williams & Davidson Attorneys Named Among 2025 ‘Best Lawyers in America,’ Deborah Willig and Irwin Aronson Named ‘Lawyer of the Year’
  • 16 Willig, Williams & Davidson Attorneys Named Among 2024 ‘Best Lawyers in America’
  • 18 Willig, Williams & Davidson Attorneys Named 2023 PA Super Lawyers & Rising Stars
  • 14 Willig, Williams & Davidson Attorneys Named Among 2023 ‘Best Lawyers in America,’ Amy Rosenberger Named ‘Lawyer of the Year’ in Philadelphia in Labor Law for Unions
  • 13 Willig, Williams & Davidson Attorneys Named Among 2022 ‘Best Lawyers in America,’ Two Named ‘Lawyers of the Year’ in Employee Benefits, Union Law
  • 17 Willig, Williams & Davidson Attorneys Named 2021 PA Super Lawyers, Managing Partner Named Among Top Attorneys in State
  • Willig, Williams & Davidson Attorney Nancy Lassen Quoted in The Philadelphia Inquirer
  • 5 Willig, Williams & Davidson Attorneys Selected as 2021 ‘Women Leaders In The Law’
  • 15 Willig, Williams & Davidson Attorneys Named Among 2021 ‘Best Lawyers in America,’ Nancy B.G. Lassen Named ‘Lawyer of the Year’ in Philadelphia Labor Law
  • Labor Attorney Nan Lassen Quoted by Vox on Regulators’ Failures to Protect Workers from COVID-19 as States Reopen
  • Nancy B. G. Lassen Elected as Fellow of the College of Labor and Employment Lawyers
  • Willig, Williams & Davidson Partners Present Webinar on Emerging Risks for Resumption of Business Operations for PBI
  • Philly Port Workers Union Pushed for Safety Precautions
  • Workers Question ‘Are We Essential or Disposable?’
  • Labor Attorney Nancy Lassen talks to NBC 10 About the Coronavirus Pandemic Endangering Meat Plant Workers
  • Labor Attorney Nancy Lassen Discusses Coronavirus Exposures and How Employees Can Protect Their Rights
  • 16 Willig, Williams & Davidson Attorneys Named 2020 PA Super Lawyers and Rising Stars
  • Willig, Williams & Davidson Lawyers Named Among 2020 ‘Best Lawyers in America’
  • 14 Willig, Williams & Davidson Attorneys Named 2019 PA Super Lawyers and Rising Stars
  • Third Circuit Rejects Employer Attempt to Shift Withdrawal Liability to Teamsters Union
  • 15 Willig, Williams & Davidson Attorneys Named Among 2019 ‘Best Lawyers in America’
  • 14 Willig, Williams & Davidson Attorneys Named 2018 PA Super Lawyers and Rising Stars
  • 14 Willig, Williams & Davidson Attorneys Named Among 2018 ‘Best Lawyers in America’
  • 13 Willig, Williams & Davidson Attorneys Named 2017 PA Super Lawyers and Rising Stars
  • Willig, Williams & Davidson Labor Lawyer Nancy B.G. Lassen provides insight on SEPTA Strike to WHYY and Newsworks
  • 12 Willig, Williams & Davidson Attorneys Named Among 2017 ‘Best Lawyers in America’
  • 12 Willig, Williams & Davidson Attorneys Named 2016 PA Super Lawyers and Rising Stars
  • 12 Willig, Williams & Davidson Attorneys Named to 2016 ‘Best Lawyers in America’
  • 11 Willig, Williams & Davidson Attorneys Named 2015 PA Super Lawyers and Rising Stars
  • Game Change: NLRB Permits College Football Players to Elect a Union

Nan Lassen’s practice at Willig, Williams & Davidson has focused exclusively on labor law since 1984. Nan has tirelessly advocated for unions—working men and women and their elected representatives—to advance their unions, wages, hours, terms and conditions of employment. Her wide-ranging skill and experience includes negotiating and enforcing collective bargaining agreements, complex litigation at every level of the state and federal courts, state and federal administrative agency proceedings, grievance and interest arbitrations, election and internal union matters, and occupational health and safety disputes. A born teacher, Nan has also spoken at countless conferences, meetings and educational forums for union officers, representatives and  members. As a highly recognized union-side attorney with more than 35 years in practice, Nan has a reputation as a strong and effective advocate for labor organizations and workers in every sector of the workforce, including public employees (uniformed and non-uniformed), federal employees, private sector and industrial workers, longshore employees and the building trades. Nan’s strategic advice and collaboration are sought after and highly valued by union leadership and representatives.

Nan grew up in Detroit, in a community with strong ties to labor. Not only was she raised in a union family, but Nan herself has been a champion of working Americans all her life. Working in industry since age 15, including on a Chrysler assembly line, Nan developed a deep commitment to unions and especially worker safety and health. As a union representative, Nan was on the front line advocating for workers long before she went to law and graduate school.

Nan is also a sought-after speaker, educating union leaders, workers, law students and attorneys in matters such as internal union election law, employment discrimination, family medical leave, occupational safety and health, advocacy and representation skills, as well as the rights and responsibilities of labor unions and union members. She was previously an Adjunct Professor of Labor Law at Drexel University’s Thomas R. Kline School of Law, and currently guest lectures by invitation.

WHAT INSPIRES ME ABOUT MY WORK

“Working for unions naturally flows from my life history. My grandfather was a Steelworker on the iron ore docks. My father was a Teamster warehouseman, and my mother was a UAW member. I was a union advocate myself before I was even out of high school. So, bringing the tools of my education and experience to advocating for working people–from building trades and blue collar to professionals and technical—is my work, and a lifelong commitment.”

  • Willig, Williams & Davidson Attorney Nancy Lassen Quoted in The Philadelphia Inquirer
  • 5 Willig, Williams & Davidson Attorneys Selected as 2021 ‘Women Leaders In The Law’
  • Labor Attorney Nan Lassen Quoted by Vox on Regulators’ Failures to Protect Workers from COVID-19 as States Reopen
  • 15 Willig, Williams & Davidson Attorneys Named Among 2021 ‘Best Lawyers in America,’ Nancy B.G. Lassen Named ‘Lawyer of the Year’ in Philadelphia Labor Law
  • Nancy B. G. Lassen Elected as Fellow of the College of Labor and Employment Lawyers
  • Willig, Williams & Davidson Partners Present Webinar on Emerging Risks for Resumption of Business Operations for PBI
  • Philly Port Workers Union Pushed for Safety Precautions
  • Workers Question ‘Are We Essential or Disposable?’
  • Labor Attorney Nancy Lassen Discusses Coronavirus Exposures and How Employees Can Protect Their Rights
  • Labor Attorney Nancy Lassen talks to NBC 10 About the Coronavirus Pandemic Endangering Meat Plant Workers
  • 16 Willig, Williams & Davidson Attorneys Named 2020 PA Super Lawyers and Rising Stars
  • Game Change: NLRB Permits College Football Players to Elect a Union
  • Willig, Williams & Davidson Labor Lawyer Nancy B.G. Lassen provides insight on SEPTA Strike to WHYY and Newsworks
  • 15 Willig, Williams & Davidson Attorneys Named Among 2019 ‘Best Lawyers in America’
  • 14 Willig, Williams & Davidson Attorneys Named 2019 PA Super Lawyers and Rising Stars
  • 14 Willig, Williams & Davidson Attorneys Named 2018 PA Super Lawyers and Rising Stars
  • 14 Willig, Williams & Davidson Attorneys Named Among 2018 ‘Best Lawyers in America’
  • 13 Willig, Williams & Davidson Attorneys Named 2017 PA Super Lawyers and Rising Stars
  • 12 Willig, Williams & Davidson Attorneys Named Among 2017 ‘Best Lawyers in America’
  • 12 Willig, Williams & Davidson Attorneys Named 2016 PA Super Lawyers and Rising Stars
  • 12 Willig, Williams & Davidson Attorneys Named to 2016 ‘Best Lawyers in America’
  • 11 Willig, Williams & Davidson Attorneys Named 2015 PA Super Lawyers and Rising Stars
  • Willig, Williams & Davidson Lawyers Named Among 2020 ‘Best Lawyers in America’
  • Third Circuit Rejects Employer Attempt to Shift Withdrawal Liability to Teamsters Union
  • 17 Willig, Williams & Davidson Attorneys Named 2021 PA Super Lawyers, Managing Partner Named Among Top Attorneys in State
  • 13 Willig, Williams & Davidson Attorneys Named Among 2022 ‘Best Lawyers in America,’ Two Named ‘Lawyers of the Year’ in Employee Benefits, Union Law
  • 14 Willig, Williams & Davidson Attorneys Named Among 2023 ‘Best Lawyers in America,’ Amy Rosenberger Named ‘Lawyer of the Year’ in Philadelphia in Labor Law for Unions
  • 18 Willig, Williams & Davidson Attorneys Named 2023 PA Super Lawyers & Rising Stars
  • 16 Willig, Williams & Davidson Attorneys Named Among 2024 ‘Best Lawyers in America’
  • 17 Willig, Williams & Davidson Attorneys Named Among 2025 ‘Best Lawyers in America,’ Deborah Willig and Irwin Aronson Named ‘Lawyer of the Year’
  • Articles + News Coverage

Education

  • Harvard University (M.S. (Occupational Physiology, Safety and Health), 1982)
  • Northeastern University School of Law (J.D., 1981)
  • University of Michigan, Residential College (B.A., 1978)
    • Phi Beta Kappa, Alpha of Michigan

Honors and Awards

  • Fellow, American Bar Foundation, 2012 - present
  • The Best Lawyers in America©, 2014 - present
  • Pennsylvania Super Lawyers (Thomson Reuters), 2004 – 2006, 2008 - present
  • Designated as a Top Rated Employment & Labor Attorney in Philadelphia
  • Fellow, College of Labor & Employment Lawyers
  • Fellow, National Institute of Occupational Safety and Health, Harvard University
  • Martindale-Hubbell® A-V Preeminent™ (peer and judicial rating), 1996 to Present

Associations

Professional

  • AFL-CIO Lawyers Coordinating Committee, 1984 to Present
  • American Bar Association, 1981 to Present
  • Philadelphia Bar Association, 1984 to Present; Labor Committee Co-Chair, 1992
  • Pennsylvania Bar Association, 1984 to Present
  • American Bar Foundation, 2012 to Present

Community

  • Adjunct Professor of Labor Law, Drexel University School of Law

Admissions

Bar Admissions

  • Pennsylvania, 1985
  • Massachusetts, 1981

Court Admissions

  • U.S. Court of Appeals for the, Seventh Circuit, 1984
  • U.S. Court of Appeals for the, Sixth, Circuit, 1984
  • U.S. District Court for the, Southern District of, Ohio, 1984
  • U.S. Court of Appeals for the, Third, Circuit, 1985
  • U.S. District Court for the, Eastern District of, Pennsylvania, 1985
  • U.S. Court of Appeals for the, Federal, Circuit, 1986
  • United, States, Supreme Court, 1986
  • U.S. Court of Appeals for the, Eleventh, Circuit, 1995
  • U.S. District Court for the, Middle District of, Pennsylvania, 2004
  • U.S. District Court for the, District of, Colorado, 2019

Judicial Clerkships

  • Chief Judge George C. Edwards, Jr., United States Court of Appeals for the Sixth Circuit, Senior Law Clerk, 1983-1984

Employment

  • Willig, Williams & Davidson, Partner, 1990-Present
  • Willig, Williams & Davidson, Associate, 1984-1989
  • Philadelphia
  • Harrisburg
  • Haddonfield
  • Chicago
  • 215.656.3600
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